Disposable syringes are widely used, for instance, for injecting medications or for removing organic liquids for therapeutic or analytical medical purposes.
Such disposable syringes are commercially available sterilized and ready for use. They include a needle, protected within a removable, rigid and protective hood or sheath.
With such syringes, however, there exists the danger of involuntary removal of the sheath from its protective position before use of the syringe with consequent danger of needle contamination as well as of accidental injury to the personnel working with syringes.
An even greater danger of injury and infection exists in the subsequent disposal of the syringes after use. In fact, if the syringes are abandoned or discarded without their proper protective sheath, they constitute a means of possible injury and consequent eventual contamination or infection to those who, casually or inadvertently, might come into contact with such used syringes. On the other hand, the very act of replacing the sheath on the needle, after use, presents the danger of possible injury and, therefore, consequent possible contamination to the user.
In any event, the presence of the protruding needle in position of use from a disposable syringe constitutes a source of serious danger or infection to those who might come into contact with the syringe.